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ViewBag don't contains items which are set in the partial view


Astazi vreau sa vorbim despre ViewBag. Daca nu l-ati folosit pana acuma, in MVC 3 acesta este un dictionar dynamic, in care se pot pune valori pentru a fi trasmise de la controller la view date. Cel mai nice lucru la el este ca este un tip de data dynamic. Cea ce inseamna ca putem sa facem get/set la date folosind propietati pe post de keys.
In loc de:
    ViewData["DateNow"] = DateTime.Now;
    ViewData["Age"] = 55;
Avem:
    ViewBag.DateNow = DateTime.Now;
    ViewBag.Age = 55;
Sa trecem la lucruri mai interesante. Daca avem un View care contine un partial view in care populam ViewBag-ul( desii nu e sanatos poate sa apara cazul acesta), o sa observam ca in view-ul parinte sau in _Layout, ViewBag-ul nostru nu contine elementele pe care le-am adaugat.
Prima reactie este sa spunem ca este sa spunem ca este un bug. Daca ne uitam putin peste cum functioneaza MVC 3 o sa descoperim ca de fapt la partial view primeste propiul sau ViewBag.
Solutia pentru a rezolva aceasta problema este sa trasmitem ViewBag-ul mai departe la partial view. Il putem trasmite ca si un ViewDataDictionary, iar apoi in partial view sa il convertim spre un tip de data dynamic.
Pagina principala:
@{Html.RenderPartial("Elaborate", Model, new ViewDataDictionary { {"vb", ViewBag}});}
….
@ ViewBag.Age=25;
 Partial view:
@{
     var viewBag = ((dynamic)ViewData["vb"]);
     viewBag.Age = 20;
}
Ce parere aveti? Vedeti alte solutii?

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